Al-Nasser Saladin Brigades, an armed wing of the Popular Resistance Committees (PRC), and the Fatah's al-Aqsa Martyrs Brigades claimed responsibility for firing two rockets at Israel's southern town of Sderot.

One rocket moderately wounded a Sderot resident while the others lightly damaged a house in the city, one km away from the Gaza Strip, according to Israel Radio.

"This holy attack came in response to Israeli crimes against our children, women and all of our people in northern and eastern Gaza Strip," the groups said in a statement.

Meanwhile, Hamas' armed wing announced that it fired six mortar shells at a position in eastern Gaza City, where Israeli tanks were massing.

Earlier, Israeli F-16 jets attacked and badly destroyed a bridge linking the northern Gaza Strip town of Beit Hanoun to the main road. The Israeli army said it was to prevent militants from transporting rockets to launch sites.

Olmert demanded that Palestinian militants free a kidnapped Israeli soldier and stop firing homemade rockets at Israeli cities before calling off the offensive.

The ongoing Gaza operation was the first major Israeli military move in the territory since Israel quit the coastal strip last summer after 38 years of military rule. Enditem

Related:Israel denies responsibility for Saturday's Gaza blast

JERUSALEM, July 9 (Xinhua) -- The Israel Defense Forces (IDF) said on Sunday that the IDF was not to blame for Saturday's explosion in a house in Gaza City that killed three members of a family, the Jerusalem Post reported.

Citing an initial investigation into the incident, the IDF confessed on Sunday that it did launch an air strike in the area, but claimed that the raid was targeting a group of armed gunmen.

Palestinians earlier blamed an IDF artillery shell for the blast in a house of a family, a charge rejected by IDF, which claimed that its artillery did not shell the area.

A huge blast occurred in a house in Gaza City on Saturday evening, killing three members of a family and wounding four.

Medics at Shiffa Hospital in Gaza City confirmed that a 42-year-old mother, her 20-year-old son and six-year-old daughter were killed by splinters of an Israeli tank shell.

Palestinian security sources said that an Israeli tank stationed in eastern Gaza City fired several shells at the city's neighborhood of Sheja'eya and one of the shells hit a house in the neighborhood. Enditem

6 Palestinians killed in Gaza Strip

GAZA, July 8 (Xinhua) -- The Palestinian death toll on Saturday rose to six during Israeli military operation in the Gaza Strip, medical sources said.

Jom'aa al-Saqqa, chief of emergency in Gaza City's Shiffa hospital, said that three were shot dead in fresh clashes with Israeli troops in eastern Gaza while the other three died of their wounds sustained in northern Gaza in the last two days.

He said that shortly after Israeli tanks and armored vehicles withdrew on Saturday morning from areas they seized in the northern Gaza town of Beit Lahia, Palestinian medics found a 19-year-old Palestinian dead.

He said that the young man was physically disable and died of his wounds sustained in an Israeli air strike on Friday.

Israeli army tanks intruded into the Shajaiyeh neighborhood on the eastern outskirts of Gaza City on Saturday morning. About seven Palestinians were killed on Friday and about 20 Palestinians and an Israeli soldier were killed on Thursday, the most bloody single day since Israel launched massive ground offensive in the Gaza Strip on June 28 to rescue an Israeli soldier kidnapped by Palestinian militants and halt rocket fired from Gaza. Enditem

Israel rejects Palestinian PM's ceasefire proposal

Black smoke is seen during an Israeli bombardment over the town of Beit Lahiya, northern Gaza Strip July 8, 2006. (Xinhua/AFP Photo)

An official in Israeli Prime Minister Ehud Olmert's office said that Israeli government would not agree to any truce until the Palestinian militant groups free kidnapped soldier Gilad Shalit and stop firing homemade rockets at Israeli cities.

As Israel intensified its offensive in the Gaza Strip, Haneya on Saturday called on Palestinian militants and Israel to halt violence in Gaza after 11 days of Summer Rain military operation left nearly 40 Palestinian militants dead.

"In order to get out of the current crisis, it is necessary that all parties restore calm on the basis of mutually stopping all military operations," a statement issued by Haneya's office in Gaza said.

The Israel Defense Forces (IDF) expanded its operation in Gaza on Saturday morning, with tanks advancing to within 500 meters of Gaza City.

Some 15 tanks entered the Strip through the Karni border crossing in what the army said was a search for tunnels used by militants.

Late Saturday afternoon, IDF troops withdrew from positions overlooking the northern Gaza town of Beit Hanun as well as the Dahaniyeh airport in the southern Gaza Strip. Enditem